Even after he admitted it?
Yes. It is very common in these cases for the mother of the child to be in total denial over what the boyfriend (it's almost never the biological father) is doing to her daughter.
The woman, you see, is so invested in keeping the man (not being bound to him by marriage) that she will cheerfully sacrifice her own daughter to keep him.
One of the nasty pieces of fallout from women living with men without benefit of a marriage license.
Such men are also far more likely to abuse and kill the woman's children -- which interestingly enough is what many male animals do, in order to maximize their own genetic potential with a new mate. Without a moral code, humans degenerate into wild animals.
Something like CHILD RAPIST Victim 10 yr old.